Dublin, United States: Former world number one Rory McIlroy came back to earth with a thud on Friday with a six-over par 78 in the second round of the Memorial.
McIlroy, who arrived at this Jack Nicklaus-hosted US PGA Tour event off a win in the European PGA Championship at Wentworth, had seized the lead with a first-round 63 on Thursday.
But after a bogey at his opening hole, the 10th, and a birdie at 12 he had double bogeys at the 13th, 14th and 15th to lie six-over for the day after his first six holes.
McIlroy three-putted the 13th from 75 feet and was in the water at 14. He almost reached the par-five 15th in two, but double-hit a chip.
A bogey at 18 saw him make the turn in seven-over 43 -- and even a second nine that included two birdies and one bogey did little to help his cause.
His 78 left him on three-under 141, nine shots off the lead of England's Paul Casey, who fired a six-under par 66 for the clubhouse lead on 12-under 132.